In order to log a find for this EarthCache you must visit the location given, make some observations and answer some questions. You may email me your answers (for a quick reply) or use the message system. You are invited to log your find at the same time as sending your answers. I will reply.
This cache is all about Garnets in the rock used to face the building. The pinkish rock is called schist, which is a type of granite.
Firstly Schist
Schist is what is known as a metamorphic rock. Metamorphic rock is the transformation of an existing rock type, the protolith, in a process called metamorphism, which means "change in form". The protolith is subjected to heat and pressure causing profound physical and/or chemical change. Schist, has flat, sheet like crystals, which are aligned in mostly the same orientation, this is due to the process of metamorphism. In many cases it can have a shiny appearance due to the presence of mica. if you look at the schist at the EarthCache location, it has an almost silvery / gold shine to it.
You are here to look for something called a Garnet.
So what are Garnets, well they are crystalline, and can be red, brown, yellow, black or green. They are formed from silicate minerals. Garnets are found in highly metamorphosed rocks and some igneous rocks. Often a deep translucent or transparent red, garnet is a popular gem. In the case of metamorphic rocks, Garnets form when the process of metamorphism, causes minerals in the protolith to break down, and then form crystals in the form of garnets.
There are many main varieties of garnets (and there are gradations between them), they occur fairly frequently in deposits scattered about the world.
Here are a few you might come across and why they are their given colour.
Almandine, is the most common of all garnets, is usually deep red to reddish brown and sometimes purplish. Due to its large iron content, it is paramagnetic (attracted to a magnet).
Pyrope, is less widely distributed but more valuable as a gemstone, is rose-red to reddish purple in colour.
Grossular garnets are yellow to brownish hue crystals typically found in contact with limestone or marble metamorphic rocks. These garnets are rich in calcium.
Spessartite garnets are a yellowy and orange colour, due to the presence of magnesium in the stone.
Andradite garnets consist mainly of iron, however due to the iron being contained in different structures in the garnet, so at times some andradite garnets sometimes can emit a diamond or yellowish colour.
This is meant to be a simple EarthCache, that allows you to see something you may not often see.
This being an EarthCache, in order to log it, I ask that you answer the following questions. Please send them to me, and do not include them in your log. You can send them to me by using the message facility or email, both of which can be found by looking at my profile.
I will read your log and tend to respond to email quicker, but you can log your find and send
So to some questions.
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At the listed co-ordinates, please describe the garnets that you find, in terms of size, colour and their concentration. By concentration I mean, are they widely spread across the rock, or are they sparsely spread across the rock?
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Using the above information, please explain what type of garnet that is here.
Thanks for attempting this cache, I hope you found it informative.
treboR